Element analyzing apparatus

Abstract

An element analyzing apparatus includes a secondary ion excitation source such as an ion gun, an ion optical system such as an imaging type energy filter and a mass spectrometer. A quadrupole mass spectrometer is used as the spectrometer. The quadrupole mass spectrometer has a construction in relation to (L×F) 2 >0.2, where L (meter) is a length of a quadrupole of the spectrometer and F (MHz) is frequency. Secondary ions emitted from a sample are accelerated to cause them to pass through the ion optical system and the quadrupole mass spectrometer under a condition with an energy more than a secondary ion energy constant in addition to an energy of the secondary ions emitting from the sample. The first mentioned energy may be ten times or twenty times the secondary ion energy constant. The element analyzing apparatus is capable of effecting the elementary analysis with high sensitivity and accuracy without lowering space resolution.

What is claimed is: 
     
       1. An element analyzing apparatus comprising: a secondary ion excitation source;   an ion optical system;   a mass spectrometer, said mass spectrometer being a quadrupole mass spectrometer having a construction fulfilling a relation (L×F) 2  >0.2, where L is a length of a quadrupole of the spectrometer and F is a frequency; and   means of accelerating secondary ions emitted from a sample and effecting the same to pass through said ion optical system and said quadrupole mass spectrometer under a condition with an energy more than a single secondary ion energy constant in addition to an energy of said secondary ions when emitted from said sample.   
     
     
       2. An element analyzing apparatus as set forth in claim 1, wherein said quadrupole mass spectrometer has a relation (L×F) 2  >1; and wherein said condition includes an energy at least more than ten times the secondary ion energy constant plus the energy of said secondary ions when emitted from said sample. 
     
     
       3. An element analyzing apparatus as set forth in claim 1, wherein said ion optical system is an imaging type energy filter. 
     
     
       4. An element analyzing apparatus as set forth in claim 2, wherein said ion optical system is an imaging type energy filter. 
     
     
       5. An element analyzing apparatus as set forth in claim 3, wherein said condition includes an energy more than at least twenty times the secondary ion energy constant plus the energy of said secondary ions when emitted from said sample. 
     
     
       6. An element analyzing apparatus as set forth in claim 4, wherein said condition includes an energy more than at least twenty times the secondary ion energy constant plus the energy of said secondary ions when emitted from said sample.